首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1162篇
  免费   74篇
  国内免费   31篇
耳鼻咽喉   17篇
儿科学   32篇
妇产科学   6篇
基础医学   106篇
口腔科学   56篇
临床医学   119篇
内科学   369篇
皮肤病学   21篇
神经病学   62篇
特种医学   75篇
外科学   119篇
综合类   8篇
预防医学   53篇
眼科学   8篇
药学   77篇
中国医学   3篇
肿瘤学   136篇
  2023年   13篇
  2022年   19篇
  2021年   34篇
  2020年   24篇
  2019年   32篇
  2018年   35篇
  2017年   25篇
  2016年   34篇
  2015年   38篇
  2014年   35篇
  2013年   39篇
  2012年   71篇
  2011年   80篇
  2010年   33篇
  2009年   43篇
  2008年   59篇
  2007年   71篇
  2006年   49篇
  2005年   41篇
  2004年   50篇
  2003年   36篇
  2002年   32篇
  2001年   27篇
  2000年   22篇
  1999年   30篇
  1998年   30篇
  1997年   22篇
  1996年   17篇
  1995年   15篇
  1994年   16篇
  1993年   18篇
  1992年   12篇
  1991年   15篇
  1990年   5篇
  1989年   11篇
  1988年   18篇
  1987年   12篇
  1986年   9篇
  1985年   11篇
  1984年   5篇
  1983年   6篇
  1982年   6篇
  1980年   7篇
  1978年   10篇
  1977年   6篇
  1976年   11篇
  1975年   4篇
  1970年   4篇
  1967年   4篇
  1965年   4篇
排序方式: 共有1267条查询结果,搜索用时 15 毫秒
1.
Technological progress and numerous published studies allow to estimate the best place of the 18F-fluorodeoxyglucose positron emission tomography, a real functional metabolic imagery, in the clinical and therapeutic strategy of non small cell lung cancers.  相似文献   
2.
This study aimed to investigate whether endothelial cells are damaged and to evaluate fibrinolytic system function in patients with type 2 diabetes. For this proposal, plasma levels of von Willebrand factor (an endothelial marker of injury), homocysteine (an inductor of endothelial injury), D-dimer (a marker of coagulation cascade activation) and plasminogen activator inhibitor-1 (a fibrinolysis marker) were measured in individuals with both type 2 diabetes and high blood pressure, with type 2 diabetes, with high blood pressure and in healthy control individuals. No significant differences among groups were observed for von Willebrand factor and homocysteine plasma levels. The type 2 diabetes and high blood pressure group presented a significant difference to the other groups for D-dimer and also presented high values for plasminogen activator inhibitor-1. The high blood pressure group and type 2 diabetes group presented separately higher values of plasminogen activator inhibitor-1 compared with the control group. High levels of D-dimer and plasminogen activator inhibitor-1 in patients with type 2 diabetes and high blood pressure with normoalbuminuria therefore indicate a state of hypercoagulability and hypofibrinolysis, despite no evident microvascular injury supported by normal levels of von Willebrand factor and homocysteine.  相似文献   
3.
4.
5.
6.
7.
The aim of our study was to compare CD3 expression on gammadelta T cells and alphabeta T cells in human patients. The antigen density of TCR and CD3 on both subsets was assessed by a quantitative method in eight patients. In parallel, we developed and validated a reliable direct tricolor staining protocol that we tested on samples from hospitalized and healthy individuals (n = 60). Our results demonstrate that human gammadelta T cells constitutively express approximately twofold more of the TCR/CD3 complex than alphabeta T cells. We suggest that this enhanced expression of the TCR/CD3 complex could contribute to the higher reactivity of gammadelta T cells compared to alphabeta T cells. These clinical laboratory results confirm the fundamental data described elsewhere. gammadelta T cells deserve further clinical investigations to understand their precise role in human immunity.  相似文献   
8.
Several lines of evidence indicate that mammalian fertilization is initiated via a binding process that is dependent upon the recognition of oligosaccharide sequences associated with zona pellucida (ZP) glycoproteins. Here, specific chemical and enzymatic methods were employed to modify human ZP and to test their effects on sperm binding in the hemizona assay system (HZA). Periodate oxidation of human ZP under very mild conditions (10 min, 0 degrees C, 1 mM sodium m- periodate) that attacks only terminal sialic acid resulted in a 30% loss of human sperm binding in the HZA [hemizona index (HZI) = 70.2 +/- 10.9, n = 22; P < 0.05]. Periodate oxidation under mild conditions (1 h, 23 degrees C, 10 mM sodium m-periodate) caused a 40% decrease in binding (HZI = 60.8 +/- 10.3; n = 24; P< 0.01). Treatment of human ZP with neuraminidase caused a substantial increase in sperm binding to human ZP (HZI = 297 +/- 45, n = 22; P < 0.01). These findings indicate that there are sialic acid dependent binding sites coexisting with binding sites that are obscured by sialic acid. To determine the periodate sensitivity of these obscured sites, hemizona were first digested with neuraminidase and subsequently subjected to mild periodate oxidation. The combined enzymatic and chemical treatments caused a 79% decrease in sperm binding compared to control hemizona (HZI = 20.7 +/- 4.4, n = 16; P < 0.001). Human sperm-ZP interaction was also increased by digestion of human ZP with endo-beta-galactosidase (HZI = 710 +/- 232, n = 14; P < 0.01), indicating that potential binding sites for spermatozoa are also obscured by lactosaminoglycan sequences. These studies support a definitive role for the involvement of ZP-associated glycans in the binding of human spermatozoa to oocytes.   相似文献   
9.
Background: Despite improved detection of mantle cell lymphoma (MCL),results of its treatment with conventional therapies remain disappointing andthe survival rate poor. The role of high-dose chemotherapy has recently beeninvestigated but no potential benefit has been clearly established. We reporthere our experience with MCL patients treated with intensive chemotherapy andautologous stem cell transplantation (ASCT).Patients and methods: Of the 16 MCL patients who received high-dosechemotherapy and ASCT beginning in 1989, six were treated in first-line and10 in sensitive relapse. Twelve of 16 patients received regimens whichincluded total body irradiation. All patients received peripheral blood stemcells (PBSC) with the exception of one, who underwent bone marrowtransplantation.Results: Three patients died of toxic effects of treatment. Three monthsafter transplant, seven achieved complete responses (CR) and two partialresponses (PR), two were stable and two had progressed. With a medianfollow-up after transplant of 22 months, five of the six surviving patientswere without progression, and three were in CR. The median times forevent-free survival (EFS) and overall survival (OS) were, respectively, 249and 317 days. The expected three-year EFS and OS were 24%. The mediansurvival after diagnosis was only 29 months. None of the criteria appeared tobe significantly associated with a better outcome, but first-lineintensification and a short delay after initial diagnosis may be favorable.Conclusion: In this study we were not able to confirm the hypotheticalbenefit of high-dose chemotherapy and PBSC transplantation in mantle celllymphoma, even though this approach may be promising in a subgroup of patient.  相似文献   
10.
Frequency and significance of anemia in non-Hodgkin's lymphoma patients   总被引:5,自引:0,他引:5  
Objectives: Retrospective evaluation of anemia frequency and its prognostic value in patients with different subtypes of non-Hodgkin's lymphoma and comparison with other clinical characteristics.Patients and methods: Anemia was defined as a hemoglobin value less than or equal to 12 g/dl for all men and women over 50 years of age, and less than or equal to 11 g/dl for women under 50 years of age. The study included 1077 adult lymphoma patients treated between 1980 and 1995 with the following histologic subtypes: 127 patients with small lymphocytic or lymphoplasmacytoid, 62 with marginal zone, 50 with mantle-cell, 208 with follicular, 104 with T-cell lymphoma, 426 with diffuse large-cell and, finally, 73 patients with other high-grade lymphomas.Results: Anemia was present in 341 patients (32%). It was an adverse prognostic factor (P <; 0.0001) for overall survival (OS) and progression-free survival (PFS) but not for relapse-free survival (RFS). When patients with and those without bone marrow involvement were considered separately, anemia remained an adverse factor. Anemia was significantly associated with shorter PFS in small lymphocytic or lymphoplasmacytoid, mantle cell, diffuse large cell and high-grade lymphomas and with shorter OS in all histologic subgroups except marginal zone lymphoma. In multivariate analysis, anemia was a significant prognostic factor for OS and PFS for the population as a whole (P = 0.0001 and P = 0.0048, respectively) and in patients with bone marrow involvement (P = 0.007 and P = 0.005, respectively) but not in patients without bone marrow involvement. Finally, the addition of anemia to the International Prognostic Index led to an improvement for OS (P = 0.0004) and PFS (P = 0.0004).Conclusions: Anemia is an important adverse prognostic factor for the outcome of lymphoma patients, particularly in some histologic subgroups and in patients with bone marrow involvement.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号